What is a parallel circuit?
A parallel circuit is one in which there are multiple paths for current to flow through.
A wire extends from a power source to a junction. At that junction, the paths diverge, allowing different devices to be connected to each path. This means that, even if one device is disconnected or will not work (for example, a burned out light bulb), the current will still flow through the other paths and the other devices will still work.
Then the various paths come back together at another junction and a wire continues the circuit back to the power source.